溶液法生长钙钛矿纳米线

Growth of Perovskite Nanowires by Solution Method

近些年,一维(1D)卤化物钙钛矿的低维纳米材料在光电探测器材料领域成为备受科学家关注的焦点之一,因其拥有优异的光吸收系数、发射效率和高载流子迁移率,长的载流子扩散长度等优秀的光电性能。本实验通过蒸发诱导自组装方法制备出钙钛矿纳米线,在保持钙钛矿溶液浓度不变的情况下,把离子液体1-丁基-3-甲基咪唑四氟硼酸(BMIMBF4)作为添加剂加入到钙钛矿纳米线中。其中设置了四组不同的BMIMBF4浓度来探究离子液体的添加对钙钛矿纳米线的影响,其中离子液体的浓度分别为0 mmol、0.1 mmol、0.3 mmol、0.6 mmol。从实验结果可以得知,加入BMIMBF4离子液体之后纳米线的PL (稳态光致发)强度更高,表明BMIMBF4对MAPbI3纳米线的生长起到一定的促进作用,提高了钙钛矿纳米线的稳定性和光电性能。其中加入0.3 mmol离子液体的促进效果最强,加入0.6 mmol离子液体的钙钛矿纳米线相对于浓度为0.3 mmol那一组的促进效果较弱,可能是由于离子液体浓度过高抑制了钙钛矿纳米线的生长。

In recent years, one-dimensional (1D) halide perovskite low-dimensional nanomaterials have become one of the focuses of scientists in the field of photode-tector materials, because of its excellent optical absorption coefficient, emission efficiency, high car-rier mobility, long carrier diffusion length and other excellent photoelectric properties. In this ex-periment, perovskite nanowires were prepared by evaporation-induced self-assembly, and ionic liquid 1-butyl-3-methylimidazo- lium tetrafluoroboric acid (BMIMBF4) was added as an additive while keeping the concentration of perovskite solution unchanged. Four groups of different concen-trations of BMIMBF4 were set to explore the influence of ionic liquid on perovskite nanowires, and the concentrations were 0 mmol, 0.1 mmol, 0.3 mmol and 0.6 mmol respectively. From the experi-mental results, it can be known that the PL (steady-state photoluminescence) intensity of nanowires is higher after the addition of BMIMBF4 ionic liquid, which indicates that BMIMBF4 can promote the growth of MAPbI3 nanowires and improve the stability and photoelectric properties of perovskite nanowires. Among them, adding 0.3 mmol ionic solution has the strongest promotion effect, and adding 0.6 mmol ionic liquid has a weaker promotion effect than the group with the concentration of 0.3 mmol, which may be due to the high concentration of ionic liquid inhibiting the growth of perovskite nanowires.